Answer:
20%
Explanation:
Population of white-tailed deer in 1991 = 25 deer per square mile
Population of white-tailed deer in 1992 = 30 deer per square mile
We have to find the percentage increase in the deer population. The formula for percentage change is:

Original value is the population in 1991 and the New value is the population in 1992.
Using the values, we get:

Thus, the deer population increased by 20% from 1991 to 1992